An endoscope is an instrument that can be used for examination and surgical modification within cavities of the body. For example, an endoscope can be configured to be inserted into the intestinal tract of a patient, such as a colonoscope that is configured for examination of the colon. The endoscope can include a digital imaging device at a distal end of the endoscope, such as a charge coupled device (CCD) light sensor. Other functionality can be provided to the endoscope, such as the ability to introduce water or air into a body cavity or to perform suction in order to remove fluids or material through the working channel of the endoscope.
An endoscope can also be configured for biopsy of tissue from the portion of the body that it is configured to examine. For example, a colonoscope can be configured for the removal of tissue from the colon, such as colon polyps that are found during a colonoscopy. A common method for removing polyps from the colon is the snare polypectomy technique, which uses a wire with a lasso-like loop that can be placed around the polyp. The loop can be tightened around the polyp and optionally can be energized to cut off and, if necessary, cauterize the location of the polyp. The polyp can then be collected through the working channel of the endoscope for later inspection.
While the snare polypectomy technique can be advantageous due to its simplicity, snares are not perfect in capturing polyps. A certain percentage of polyps can be lost within the body cavity, which can lead to difficulty in locating and retrieving the lost polyp.